Device for vaporizing unatomized fuel



I J. W SMITH DEVICE FOR VAPORIZING UNATOMIZED FUEL 2 eets-Sheet 1 Filed y 26. 1921 I M I w M a w WWW-5525. 62 I fi M .2 val, i .0

May 24,.1927.

WITNESSES 1,629,975 J. w. SMITH DEVICE FOR VAPORIZING UNATOMIZED FUEL Filed July 25. 1921 2 Sheets-Sheet 2 INVENTOR: 7 @7212 W Smizh,

ATTORNEYS;

Patented May 24,1927.

JDHN W. SEITH, F PHILADELPHIA, PENNSYLVANIA.

DEVICE FOR VAPORIZING ,UNA'IOMIZED FUEL.

Application filed July 26,

The invention relates to devices forvapon. izing unatomized fuel separated from the fuel stream used in propulsion of internal combustion engines.

Complete vaporization of commercial liquid fuels at the present time available for propulsion of internal combustion motors is, as is well known, impossible with the ordinary carburetor, so that a large portion of the fuel is but partly consumed and wasted by discharge, in the form of carbon, throu h the exhaust of the motors. This is due to t 1e fact that such fuels are complex in their composition; i. e., certain portions thereof is (the low end point content) readily vaporize at ordinary temperatures while other portions (the high endpoint content) require considerable heating before vaporization can be effected. Numerous devices have heretofore been designed wherein the whole of the fuel mixture (air and atomized liquid fuel) is raised to the temperature required for its complete evaporation, but with the disadvantage that the efliciency of explosion of the gas is greatly reduced when used in the motors. a

The paramount object of my invention is tosecure a completely vaporized fuel mixture at the lowest. possible temperature, and 80 this desideratum I attain by aid of a novel vaporizing device adapted for use in association with standard types of carburetors and wherein only that portion of the fuel which will not readily evapora'teat ordinary temperatures, is heated and, after being vaporized, is commingled with the more volatile content in the course of delivery to the motor which is to be supplied.

Other objects of my invention are to render it possible to effect in a device of the type referred to, separation of the greater portion of the unevaporated liquid fuel from the main' charge without necessitating any movable parts; and to secure absolute simplicity in construct-ion with a view toward theutmost economy in manufacture.

Further objects and attendant advantages of my invention will become readily apparent from the detailed description which follows. i

In the drawings Fig. I is a plan view of a vaporizing device representatlvevof'my invention in a. suitable ,form for accomplishing the ends above pointedout.

Fig. II is an elevation of the structure, with portions thereof shown in section so as 1921. Serial in. 487,811.

to set forth more clearly certain important details of construction.

Flg. III is a similar view of a tubular insert element forming part of the device; and

Fig. IV is a detail plan section viewed in the direction of the arrows IVIV in Fig. III.

In the organization shown in the draw- 7 ings, 1 designates a carburetor of a standard type,'2, the intake manifold of an internal combustion engine, and 3, a fuel vaporizing device typical of my invention. This device 3, it will be noted, is generally in the form of a conduit and is interposed, in axial continuity between the outlet neck 4 of the carburetor 1 an'dthe inlet 5 015 the fuel intake manifold so that the entire combustible mixture of fuel and air, after leaving said carburetor, isobliged to pass through the same en route to the cylinders of the motor which is to be supplied. The casing or shell 6 of the device 3 may be made as aseparate element capable of being inserted through an appropriate opening in the exhaust manifold 7 of the motor, or as an integral part of the manifold 2 as suggested so that the heat of the exhaust may be uti-.

lized in vaporizing the more sluggish high end point content of the fuel, as will be explained in detail later herein. The greater portion of the shell 6 is disposed or jacketed within a bulged portion 8, of the exhaust manifold 7 and has there formed about it a series of encircling heat'condncting fins 9. The bore of the shell 6 is substantially of uniform diameter except where interrupted by an inwardly extending circumferential, subdividing protuberance or flange 10, which serves to set apart a mixing chamber 11 in the lower portion of the shell extending to the exterior of the exhaust manifold.

Axially disposed within the upper portion of the bore of the shell 6 is an insert element 12 which is illustrated separately and on an enlarged scale in Fig. III of the drawings. As there shown, it will be observed that this insert element 12 comprises a sleeve 13, whose upper end fits snugly both within'the inlet neck 5 of the intake manifold 2, and the mouthof the bore of. the shell 6. This sleeve13 also has an integral external flange 1 1 which is clamped, with interposition of suitable packing washers 15--15, between the end of the neck 5 and a boss 16 on the top of the exhaust manifold 7. The lower end of the sleeve 13 conforms in configuration with p the bore of the shell 6 as clearly shown in Fig. II, but is of slightly lesser diameter so as to provide a narrow annular interspace, or auxiliary passage 20 which merges into an enlarged cavity 21 formed by a recession 22 in said sleeve. Within the sleeve 13 is secured a tubular element 23 which affords whatI will term for convenience, a main passage 24 for the flow of the fuel mixture through the vaporizer 3. The lower extremity of the element 23 protrudes through the end of the sleeve 13 and extends slightly beyond the protuberance 10 so as to afford an annular trap 25 whereby unvaporized liquid fuel accumulating on the wall of the mixing chamber 11, is trapped and directed into the auxiliary passage 20 under assistance of the suction created by the action of the cylinders of the motor. Within the top of the element 23 is secured a second but shorter tubular element 26 whose lower end is reduced in diameter as shown at 27 and constitutes a supplemental trap for collecting any unvaporized fuel which may find its way into the main passage 24 and directing the same through openings 28 in the element 23 and the sleeve 13 into the enlarged cavity 21 of the auxiliary passage 2O previously referred to. This cavity 21 is communicative with the intake manifold 2 through openings 29 in the sloping portion of the sleeve 13 nearest the top of the latter. It is to be particularly noted that a difference of pressure will be maintained betweenthe mixing chamber 11 and the intake manifold 2 brought about by the nozzle effect of the relatively different diameters of the sleeve elements 23 and 26, thus effecting upward circulation through the auxiliary passage 20 as hereinbefore mentioned. In order to prevent radiation of heat from the exhaust manifold 7 to the main passage 24 of the conduit or insert element 12, the sleeve 13 and the tubular element 26 are recessed as at 30 and 31 respectively, the recessions being filled with a suitable thermo-insulaitory material such,

for example, as asbestos fiber or the like.

The operation of the device is as follows: The liquid fuel is atomized and at the same time mixed with air under the characteristic functioning of the carburetor 1 in the well known manner, and delivered through the neck 4 of the latter under control of the throttle valve shown at 32. As the fuel enters the mixing chamber 11, a certain amount of turbulence is set up through automatic retardation of the flow, due to the larger diameter of the mixing chamber 11 as compared with that of the carburetor outlet. This turbulence is restricted more or less to a gyratory path through impact of the mixture against the throttle 32 so that the portion of the fuel. not readilv vaporized by this action at ordinary temperatures, is

- thrown against and deposited as condensation along the inner surface of the mixing chamber 11. The upward draft through the conduit causes such liquid accumulation to be drawn along the slightly sloping wall of the mixing chamber 11 and into the trap 25 about the lower end of the tubular element 23. On account of the substantial difference in cross sectional area between the main passage 24 through the tubular element 23 and the auxiliary passage 20, the velocity of the vaporized fuel in passing through said main passage is many times greater than that of the draft through said auxiliary passage, with the result that the liquid fuel is drawn through said passage very much slower, relatively speaking, so as to afford ample time for evaporation under the action of the heat from the exhaust manifold 7. Such vaporization escapes first into the larger cavity 21 of the auxiliary passage 20,

thence through the openings 29 in the sleeve 13 and finally into the neck 5 of the intake manifold 2 to commingle with the main flow passing through the conduit or insert element 12. Any accumulation which gathers on the inner surface of the shell 23 is diverted, as. hereinbefore' described, through the openings 28 into the enlarged cavity 21 of the auxiliary passage and trickles downward into the narrower portions of said passage so as to be vaporized in a manner already understood. The cavity 21 is made purposely larger in area than the auxiliary passage 20 so that the circulation at this point is substantially retarded to prevent the liquid discharged to said cavity from being drawn out before it has been vaporized.

laying thus described my invention, I claim:

1. A vaporizing device in the form of a axial passage for the readily vaporized con-' tent of the admixture; and the aforesaid pipe connection providing a concentric relatively restricted annular passage exterior to the sleeve conduit wherein the unvaporized portion of the admixture is trapped and vaporized for commingling with the main flog beyond said outlet of the conduit aforesai 2. A vaporizing device in the form of a conduit through which an explosive mixture is drawn; means for heating said conduit; and an insert main flow element for the lowend point content of the mixture with an intermediate perforate 'portion affording a cavity functional to divert any unvaporized portion collecting within said main flow element; said conduit and main flow element jointly affording an annular restricted passage surrounding the latter into which the unevaporated high-end point content of the I conduit through which a mixture of air and atomized fuel is drawn, said conduit affording a mixing passage for the readily vaporized low-end point content of the fuel; means for heating the conduit; an insert tubular element functioning to divert unvaporized fuel collecting below the same; and a restricted auxiliary element within the tubular element below which any remaining unevaporated content of the fuel is trapped and diverted for vaporization before commingling with the main flow at the conduit outlet; and thermo-insulating material jacketing the walls of the tubular and auxiliary elements to prevent conduction of heat into the main axial passagev aforesaid. v

4. A vaporizing device in the form of a conduit through which a fuel mixture is drawn, said conduit embodying. a mixing chamber for the readily vaporized low-end point content of the fuel; means for heating the conduit; an insert tubular element functioning to divert any unvaporized fuel collecting thereabout; a relatively shorter insert providing an annular restriction wherein any. further remaining uneva orated content of the fuel is trapped and diverted; and an annular passage having an intermedlate larger cavity exterior tothe tubular element for collecting and vaporizing those portions of unevaporated fuel diverted thereinto with provision for directing the resultant vapor back into the main flow beyond the outlet end of the conduit aforesaid.

5. A vaporizing device in the form of a conduit through which a mixture of air and liquid fuel is drawn, the lower portion of said conduit being set apart as a mixing chamber wherein the normal flow is tempo rarily retarded to effect a state of turbulence in the passing mixture to facilitate separation of any unevaporated content; means for heating the conduit; a main insert element of smaller diameter leading axially from said mixing chamber for conducting therefrom the readily vaporized low-end point content; said element also serving to divert any unvaporized fuel from the mixing chamber into a comparatively narrow auxiliary exterior passage wherein the' unevaporated fuel content is trapped and vaporized before commingling with the main flow at the conduit outlet; and a second interfitted relatively shorter tubular element for diverting any remaining unvaporized fuel collecting within the main insert element for vaporization in the exterior passage aforesaid.

6. A vaporizing device in the form of a conduit through-which a mixture of air and liquid fuel is drawn, a portion of said conduit being set apart asa mixing chamber wherein the flow is temporarily retarded to set up a state of turbulence in the passing mixture to facilitate separation and permit depositing. of the unevaporated liquid or high end point content of the fuel upon the walls of the mixing chamber; means for heating the conduit; a main passage of smaller diameterleading axially from the mixing chamber for conducting therefrom the readily vaporized low end point content a comparatively narrow auxiliary passage surrounding said main passage wherein the unevaporated liquid is trapped and heated to the point Ofvaporization in preparation for commingling with the main flow through the conduit; means for collecting the liquid accumulation in the mixing chamber and diverting the same to the auxiliary passage; and a tubular element fitted in the conduit for collecting and diverting to said auxiliary passage any unevaporated fuel which may find its way into the aforesaid main'passage. I 7. A vaporizing device in the form of a conduit, through which a mixture of air and liquid fuel is drawn; means for heating the conduit; a tubular element fitted in said conduit with provision of a surrounding relatively narrow interspace wherein any unevaporated fuel divertedethereinto from the main flow is vaporized, said tubular element functioning as a main flow passage for the readily vaporized low-end point content of the fuel; an auxiliary insert constituting an i 8. A vaporizing device in the form of a I conduit through which a mixture of air and liquid fuel is drawn, the bore of said conduit being interrupted, at an intermediate point, by an inwardly extending circumferential protuberance or flange, to set apart at one end of the tube, a mixing chamber; a tubular element disposed axially within the opposite end of the conduit bore with provision of a narrow annular intervening interspace or auxiliary passage, said tubular element projecting slightly beyond the. aforesaid flange into the mixing chamber to afford, by cooperation with the flange, a trap for collecting the unevaporated liquid accumulatmg on the inner wall of the mixing t chamber and diverting the'same to the aforesaid auxiliary passage; and a jacket surrounding the conduit throughout the extent of the auxiliary passage, for circulation of a suitable heating medium whereby the trapped liquid is vaporized in preparation for commingling with the main flow through the conduit.

9. A vaporizing device in the form of a conduit through which'a mixture of air and liquid fuel is drawn, the bore of said conduit being interrupted at an intermediate point, by an inwardly extending circumferential protuberance or flange, to set apart, at one end of the tube, a mixing chamber; a tubular element disposed axially within the opposite end of the conduit bore with provisionof a narrow annular intervening interspace, or auxiliary passage, said tubular element projecting slightly beyond the aforesaid flange into the mixing chamber to afford, by cooperation with the flange, a trap for collecting the unevaporated liquid accumulating on the wall of the mixing chamber and diverting the same to the aforesaid auxiliary passage; means for heating the conduit throughout the extent of the auxiliary passage, so that the trapped liquid is vaporized in preparation for commingling with the main flow through the conduit; and additional means for collecting any accumulation of the unvaporized liquid which may find its way'into the main flow passage and for diverting the same through openings in the wall of that passage into said auxiliary means for heating the conduit throughout the extent of the auxiliary passage; a tube sustained within the sleeve with one extremity protruding through the inner end of the sleeve and projecting beyond the aforesaid flange into the mixing chamber to afford, by cooperation with the flange, a trap shorter tube secured within the first and having its inner end reduced to afford an annular trap whereby any liquid which may find its way into the main passage is collected and diverted through the openings in the first mentioned tubular element into the enlarged cavity of said auxiliary passage.

11. A vaporizing device in the form of a conduit through which a mixture of air and liquid fuel is drawn, the bore of said conduit being interrupted at an intermediate point by an inwardly extending circumferential protuberance or flange, to set apart at one end of the bore, a mixing chamber; a sleeve disposed axially within the opposite end of the tube, said sleeve being appropriately configured to afford provision of a narrow annular interspace, which merges, at its discharge end, with a larger cavity; means for heating the conduit throughout the extent of the auxiliary passage; a tube sustained within the sleeve with one extremity protruding through the inner end of the sleeve and projecting beyond the aforesaid flange into the mixing chamber to afford, by cooperation with the flange, a trap for collecting the unevaporated liquid accumulating on the inner wall of the mixing chamber and diverting the same to the aforesaid auxiliary passage; a second and shorter tube secured within the first and having its inner end reduced to afford an annular trap whereby any liquid which may find its way into the main passage is collected and diverted through the openings in the first mentioned tubular element into the enlarged cavity of said auxiliary passage; and thermo-insulatory material acked in cavities of the aforesaid sleeve an the last mentioned tubular element for preventing radiation of heat into the main passage through the conduit.

In witness whereof, I have hereunto signed my name at Philadelphia, Pennsylvania, this 19th day of July, 1921.

JOHN W.-SMITH. 

